% Copyright 2020 Makani Technologies LLC
%
% Licensed under the Apache License, Version 2.0 (the "License");
% you may not use this file except in compliance with the License.
% You may obtain a copy of the License at
%
%      http://www.apache.org/licenses/LICENSE-2.0
%
% Unless required by applicable law or agreed to in writing, software
% distributed under the License is distributed on an "AS IS" BASIS,
% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
% See the License for the specific language governing permissions and
% limitations under the License.

function sys = pid2ss(pid)
  % Convert a PID system into a state-space model with an explicit
  % velocity input.
  sys = ss(0, [1, 0], ...
           pid.Ki, [pid.Kp, pid.Kd]);
end